In general, lunch boxes or side dishes, etc. come in a packaging body sealed airtight in a container made of resins so as to prevent foreign matter from coming in it, or to prevent food quality from decreasing. A method in which food is heated in a packaging body by a microwave oven to be cooked is widespread.
However, when food is heated while being sealed airtight in a container, the container may be expanded outward by vapor produced from the food, and be damaged. In addition, fermented food such as kimchi discharges carbon dioxide according to the degree of fermentation, and thus the container may be damaged even when the container is not heated.
In recent years, considering such problems, a container has been developed that can discharge vapor or carbon dioxide produced from food to the outside.
A food cooking container according to the related art is disclosed in Korean Patent No. 10-1391841 entitled, “Food cooking container structure having steam hole” registered by the applicant of the present invention in an earlier filing.
The food cooking container provided with a steam hole is configured to be open at an upper part thereof so as to enable food storage, and the food cooking container provided with a flange surface formed along an upper rim includes: a main sealing protrusion part formed to protrude from the flange surface to a predetermined height along the flange surface so as to be adhered to a cover film for inner sealing; an auxiliary sealing protrusion part formed on the flange surface inside the main sealing protrusion part so as to be adhered to the cover film, the auxiliary sealing protrusion part being connected to the main sealing protrusion part at opposite ends thereof so as to define a discharge space; the steam hole formed on the flange surface having the discharge space defamed thereover to enable discharge of vapor to the outside.
According to the food cooking container, after vapor in the container is discharged through the steam hole to an outside, an internal pressure of the container tends to become lower than external pressure. Accordingly, after being heated, the container may be dented inwards. To solve the above-mentioned problem, a food cooking container according to the present invention has been developed, in which the container is provided with a protrusion guide and an open groove on an inner side of a flange surface such that after vapor is discharged to the outside through a discharge hole, outside air is supplied into the container through the discharge hole, thereby preventing the container from being dented inwards after being heated.